题目 A linked list is given such that each node contains an additional random pointer which could point to any node in the list or null. Return a deep copy of the list. 分析 实现一个链表的深拷贝,返回拷贝后的新链表. 若是普通链表,逐个拷贝原始链表节点并连接即可,只需O(n)的时间复杂度:但是此题特殊的是,每个节点都有一个rando…

133. Clone Graph Clone an undirected graph. Each node in the graph contains a label and a list of its neighbors. OJ's undirected graph serialization: Nodes are labeled uniquely. We use # as a separator for each node, and , as a separator for node lab…

Copy List with Random Pointer A linked list is given such that each node contains an additional random pointer which could point to any node in the list or null. Return a deep copy of the list. 题目意思: 深拷贝一个给定的带random指针的链表,这个random指针可能会指向其他任意一个节点或者是为nu…

Copy List with Random Pointer 题解 原创文章,拒绝转载 题目来源:https://leetcode.com/problems/copy-list-with-random-pointer/description/ Description A linked list is given such that each node contains an additional random pointer which could point to any node in the…

题目 Follow up for H-Index: What if the citations array is sorted in ascending order? Could you optimize your algorithm? 分析 同LeetCode(274)H-Index第二个版本,给定引用数量序列为递增的:这就省略了我们的第一个排序步骤: O(n)的时间复杂度,遍历一次即可. AC代码 class Solution { public: int hIndex(vector<int>…

题目 Given an array of integers, find out whether there are two distinct indices i and j in the array such that the difference between nums[i] and nums[j] is at most t and the difference between i and j is at most k. 分析 题目描述:给定一个整数序列,查找是否存在两个下标分别为i和j的元…

题目 Follow up for "Find Minimum in Rotated Sorted Array": What if duplicates are allowed? Would this affect the run-time complexity? How and why? Suppose a sorted array is rotated at some pivot unknown to you beforehand. (i.e., 0 1 2 4 5 6 7 migh…

题目 Say you have an array for which the ith element is the price of a given stock on day i. Design an algorithm to find the maximum profit. You may complete as many transactions as you like (ie, buy one and sell one share of the stock multiple times).…

题目 Given a binary tree struct TreeLinkNode { TreeLinkNode *left; TreeLinkNode *right; TreeLinkNode *next; } Populate each next pointer to point to its next right node. If there is no next right node, the next pointer should be set to NULL. Initially,…

题目 Given a binary tree and a sum, find all root-to-leaf paths where each path's sum equals the given sum. For example: Given the below binary tree and sum = 22, 分析 本题目与上一题LeetCode(112) Path Sum虽然类型相同,但是需要在以前的基础上,多做处理一些: 与Path Sum相比,本题是求出路径,所以,在找到满足的路…